OREGON STATE UNIVERSITY

Hilker, Thomas

Assistant Professor

Office Location: 
Peavy 231
Phone: 
541-737-2608
541-737-4316 (Fax)
Email Address: 
Curriculum Vitae: 
Education: 

PhD, 2008, Forestry, University of British Columbia
MS, 2002, Photogrammetry and Geoinformatics, HfT Stuttgart
BS, 2000, Forestry, University of Applied Sciences, Göttingen

Areas of Interest: 
  • Remote sensing of vegetation responses to global change, carbon and water cycling
  • Monitoring of land surface cover and disturbance
  • Estimating vegetation structure using airborne and terrestrial LiDAR
  • Data assimilation of plant productivity
  • Satellite remote sensing of tropical rainforests
Current Programs: 

Current Graduate Students

  • Célio Helder Resende de Sousa (Ph.D student, primary advisor)
  • Erick McAdam (MS, primary advisor)
  • David Mildrexler (PhD) - secondary advisor
  • Justin Braaten (PhD) - secondary advisor

Exchange Students

  • Yhasmin Mendes De Moura (INPE, Brazil)
  • Javier Pacheco Labrador (PhD student, Madrid, Spain)
  • Aramde Fetene (PhD student, Addis Ababa, Ethiopia)

Previous Graduate Students

  • Martin van Leeuwen (PhD) - secondary advisor, completed in 2013
  • Wendy Peterman (PhD) - secondary advisor, compelted in 2014

Research Interests:

My major research interest is in remote sensing of the carbon, water and energy balance of terrestrial ecosystems. I use remotely sensed observations from towers and satellites to obtain information about vegetation carbon uptake over land and relate this data to models of the carbon, water and energy cycle regionally and globally. A central aspect of my work has been to scale stand level observations to the landscape where it can be observed by satellites. This includes links between vegetation structure and function, which can be obtained for instance using multi-angle optical systems, but also from airborne and terrestrial laser scanning (LiDAR) data.

I am also interested in studying changes in vegetation and vegetation cover over time using time series of satellite data. This research includes mapping of land cover and land use change and ecosystem disturbance as well as degradation of vegetation over time.

My research is very much interdisciplinary in that it builds on mechanistic approaches based on plant physiology, ecosystem and atmospheric science and I encourage collaborations across related earth science fields.

Prospective Graduate Students:
If you are interested in the area of my research or bring new ideas of research you would be interested in pursuing, please contact me directly.

Recent Publications: 

2014

  1. Hilker, T. Lyapustin, A.I., Hall, F.G., Myneni, R., Knyazikhin, Y., Wang, Y., Tucker, C.J., Sellers, P.J. On the measurability of change in Amazon vegetation from MODIS. Remote Sensing of Environment, under review
  2. Hilker, T., Lyapustin, A., Tucker, C.J., Hall, F.G, Myneni, R.B., Wang, Y, Bi, J, Sellers, P.J. Vegetation dynamics and rainfall sensitivity of the Amazon, PNAS, under Review
  3. Hilker, T., Hall, F.G., Coops, N.C., Black, T.A., Jassal R.S., Mathys, A., Grant, N.F. (2014) Potentials and limitations for estimating daytime ecosystem respiration by combining tower-based remote sensing and carbon flux measurements. Remote Sensing of Environment, 150, 44-52
  4. Hilker, T., Natsagdorj, E., Waring, R.H., Lyapustin, A.I., Wang, Y. (2014) Satellite observed widespread decline in Mongolian grasslands largely due to overgrazing. Global Change Biology, 20 (2), 418-428
  5. Lyapustin, A., Wang, Y, Xiong, X., Meister, G., Platnick, S., Levy, F.B., Korkin, S., Hilker, T., Tucker, C.J,Hall, F.G., Sellers, P.J., Wu, A. Angal, A. Science Impact of MODIS C5 Calibration Degradation and C6+ Improvements. Remote Sensing of Environment, under review
  6. Waring, R.H. Coops, N.C. Mathys, A. Hilker, T. (2014) Process-based modeling to assess the effects of recent climatic variation on site productivity and forest function across western North America. Forests, 5(3), 518-534
  7. Fetene, A., Hilker, T., Yeshitelaa, K., Prasse, R., Cohen, W., Yang Z. Detecting trends in protected area disturbance and recovery using yearly Landsat time series: The case of Nech Sar National Park, Ethiopia. Ecological Indicators, under Review
  8. Fetene, A., Yeshitelaa, K., Prasse, Hilker, T.,(2014) Effects of habitat change and habitat disturbance on the abundance and distribution of terrestrial large sized mammals of Nech Sar National Park, Ethiopia
  9. White, C.F, Coops, N.C., Nijland, W., Hilker, T., Nelson, T., Wulder, M.A. Nielsen, S.E.,  Stenhouse, G. Characterizing a Decade of Disturbance Events using Landsat and MODIS Satellite Imagery in Western Alberta, Canada for Grizzly Bear Management, submitted
  10. Fetene, A., Yeshitelaa, K., Prasse, R., Hilker, T. (2014) Analysis of landscape pattern and habitat structure of Nech Sar National Park, Ethiopia Ecologia Siencealert, in press
  11. Coops, N.C., Hilker, T., Achim, A., van Leeuwen, M., Wulder, M.A. (2014). The role of LIDAR technology for improved prediction of forest composition, structure and wood quality. Submitted to Annals for Forest Science.
  12. v. Leeuwen, M., Coops, N.C., Hilker, T., Black, T.A., Wulder, M.A. (2014) Using stochastic ray tracing and eddy-covariance gross primary productivity estimates to infer leaf level physiological parameters. Agricultural and Forest Meteorology, in press
     
    2013
     
  13. Hilker, T., Hall, F. G., Coops, N.C., Collatz, J.G., Black, T.A., Tucker, C.J., Sellers, P.J., Grant, N, (2013) Remote senings of transpiration and heat flyxes using multi-angle observations.  Remote Sensing of Environment, 137, 31-42
  14. Hilker, T., Frazer, G.W., Coops, N.C., Wulder, M.A., Newnham, G.J., Stewart, J.D., van Leeuwen, M., Culvenor, D.S. (2011). Prediction of Wood Fiber Attributes from LiDAR-derived Foreat Canopy Indicators. Forest Science 59 (2), 231-242
  15. van Leeuwen, M., Coops, N.C., Hilker, T., Wulder, M.A., Newnham, G.J., Culvenor, D.S. (2013). Automated reconstruction of tree and canopy structure for modeling the internal canopy radiation regime. Remote Sensing of Environment 136, 286-300
  16. Fu, D., Chen, B., Wang, J., Zhu, X., Hilker, T.  An improved image fusion approach based on enhanced spatial and temporal adaptive reflectance fusion model. Remote Sensing 5 (12), 6346-6360
  17. White, C., Coops, N.C., Nijland, W., Hilker, T., Wulder, M.A., Nielsen, S., Stenhouse, G. Characterizing disturbance type of high temporal landscape change for one decade of satellite imagery in western Alberta.
  18. Brown, N.D.A., Nelson, T., Bater, C.W., Coops, N.C., Hilker, T., Gaulton, R., Stenhouse, G.B. Effects of forest disturbance age on habitat use by Grizzly Bears (Ursus Arctos L.) in West-Central Alberta, Canada. Remote Sensing, under review

      
    2012

  19. Hilker, T. Coops N.C, Culvenor D.S., Newnham G., Jupp D.L.B., Siggins, A., Bater, C.W. (2012) Merging multiple terrestrial LiDAR data for vegetation analysis: Extracting terrain information. Remote Sensing Letters, 3:3 239-247
  20. Hilker, T., Coops, N.C., Gaulton, R., Wulder, M.A., Cranston, J., Stenhouse, G. (2012).   Bi-weekly disturbance capture and attribution: A case study in western Alberta. Journal of Applied Remote Sensing, 5 053568-1- 053568-11
  21. Hilker, T., Hall, F.G.,  Tucker, C.J., Coops, N.C., Black, T.A., Nichol, C.J., Sellers, P.J., Barr, A., Hollinger, D.Y., Munger, W. (2012) Data assimilation of photosynthetic light-use efficiency using multi-angular satellite data: II Model implementation and validation. Remote Sensing of Environment, 121 287–300
  22. Hilker, T., Lyapustin, A.I., Tucker, C.J., Sellers, P.J., Hall, F.G., Wang, Y (2012) Remote Sensing of Tropical Ecosystems: Atmospheric Correction and Cloud Masking Matter. Remote Sensing of Environment 127, 370–384
  23. Brown, N.D.A, Nelson, T., Bater, C.W., Coops, N.C., Hilker, T., Gaulton, R., Stenhouse, G.B. (2012) Effects of forest disturbance age on habitat use by Grizzly Bears (Ursus Arctos L.) in West-Central Alberta, Canada. Journal of Applied Remote Sensing
  24. Chen, G., M.A. Wulder, J.C. White, T.H. Hilker, and N.C. Coops. (2012). Lidar calibration and validation for geometric-optical modeling with Landsat. Remote Sensing of Environment, 124, 384-393.
  25. Coops, N.C., Hilker, T., Bater, C.W., Wulder, M.A., Nielsen, S.E., McDermid, G., Stenhouse, G. (2012). Linking ground-based to satellite-derived phenological metrics in support of habitat assessment. Remote sensing Letters, 3:3 191-200
  26. Coops, N.C., Waring, R.H., Hilker, T. (2012) Prediction of Soil Properties using a Process-based Forest Growth Model to Match Satellite-Derived Estimates of Leaf Area Index. Remote Sensing of Environment, 126, 160-173
  27. Hall, F.G., Hilker, T., Coops, N.C. (2012) Data assimilation of photosynthetic light-use efficiency using multi-angular satellite data: I. Model formulation. Remote Sensing of Environment, 121, 301–308
  28. Lyapustin, A.I., Wang, Y., Lazlo, I., Hilker, T., Hall, F.G., Sellers, P.J., Tucker, C.J., Korkin, S.V. (2012) Multi-Angle Implementation of Atmospheric Correction for MODIS (MAIAC). Part 3: Atmospheric Correction. Remote Sensing of Environment 127, 385–393
  29. Wulder, M.A., J.C. White, R.F. Nelson, E. Næsset, H.O. Ørka, N.C. Coops, T. Hilker, C.W. Bater, & T. Gobakken. (2012) Lidar sampling for large-area forest characterization: A review. Remote Sensing of Environment, 121, 196-209
     
    2011
     
  30. Hilker, T., Coops, N.C., Hall, F.G., Nichol, C.J, Lyapustin, A., Black, T.A., Wulder, M.A., Leuning, R., Barr, A., Hollinger, D.Y., Munger, J. W., Tucker, C. J. (2011) Inferring terrestrial photosynthetic light use efficiency of temperate ecosystems from space. Journal of Geophysical Research. Vol. 116, G03014. 11p.
  31. Hilker, T., Coops, N.C., Newnham, G., v. Leeuwen, M., Wulder, M.A., Stewart, J., Culvenor, D.S. (2011) Comparison of terrestrial and airborne LiDAR in describing stand structure of a thinned lodgepole pine forest  Journal of Forestry, 110, 97-104
  32. Hilker, T., Hall, F.G., Coops, N.C., Lyapustin, A., Wang, Y., Grant, N, Nesic, Z., Black, Wulder, M.A., T.A., Kljun, N., Chasmer, L., Hopkinson, C. (2010).  Remote sensing of photosynthetic light use efficiency across two forested biomes: Spatial scaling. Remote Sensing of Environment, 114, 2863–2874
  33. Hilker, T., Lepine, L., Coops, N.C., Jassal, R.S., Black, T.A., Wulder, M.A., Ollinger, S.O., Tsui, O., Day, M. (2011). Assessing the impact of N-fertilization on biochemical composition and biomass of a Douglas-fir canopy – a remote sensing approach. Agricultural and Forest Meteorology, 153, 124-133 
  34. Hilker, T., v. Leeuwen, M., Coops, N.C., Wulder, M.A., Newnham G., Jupp D.L.B., Culvenor D.S (2010). Comparing canopy metrics derived from terrestrial and airborne laser scanning in a Douglas-fir dominated forest stand Trees-Structure and Function, DOI 10.1007/s00468-010-0452-7
  35. Bater, C.W., Wulder, M.A., Coops, N.C., Nelson, R.F., Hilker, T., & Naesset, E. (2011). Stability of Sample-Based Scanning-LiDAR-Derived Vegetation Metrics for Forest Monitoring. Ieee Transactions on Geoscience and Remote Sensing, 49, 2385-2392
  36. Coggins, S.B., Coops, N.C., Hilker, T. Wulder, M.A. (2011) Augmenting forest inventory attributes with Landsat imagery in support of area-wide susceptibility assessments to bark beetle infestations. Int.J. Appl. Earth Observation & Geoinformation, in press
  37. Gaulton, R., Hilker, T., Wulder, M.A., Coops, N.C., Stenhouse, G. (2011).  Characterizing stand replacing disturbance in western Alberta Grizzly bear habitat using a satellite-derived high temporal and spatial resolution change sequence. Forest Ecology and Management 261, 865–877
  38. Hall, F.G., Hilker, T., Coops, N.C. (2011) Photosynthat, Photosynthesis from space: Theoretical foundations of a satellite concept and validation from tower and spaceborne data. Remote Sensing of Environment, 115, 1918-1925
  39. van Leeuwen, M., Hilker, T., Coops, N.C., Frazer, G., Wulder, M.A., Newnham, G.J., & Culvenor, D.S. (2011). Assessment of standing wood and fiber quality using ground and airborne laser scanning: A review. Forest Ecology and Management, 261, 1467-1478
     
    2010
     
  40. Hilker, T., Gitelson, A., Coops, N.C., Hall, F.G., Black, T.A. (2010) Tracking plant physiological properties from multi-angular tower-based remote sensing. Oecologia 165: 865-876 DOI 10.1007/s00442-010-1901-0
  41. Hilker, T., Nesic, Z., Coops, N.C., & Lessard, D. (2010).  A new automated multi-angular radiometer instrument for tower based observations of canopy reflectance (AMSPEC II). Instrumentation Science and Technology, 38, 319-340
  42. Bater, C.W., Coops, N.C., Wulder, A., Hilker, T., Nielsen, S., McDermid, G., Stenhouse, G. (2010) Using digital time-lapse cameras to monitor species-specific understorey and overstorey phenology in support of wildlife habitat assessments. Environmental Monitoring and Assessment, DOI 10.1007/s10661-010-1768-x
  43. Coops, N.C., Hilker, T., Hall, F.G., Nichol, C., Drolet, G.G. (2010) Estimation of Light-Use-Efficiency from Space: A Status Report. Bioscience, 60, 788-797
  44. Watts, J., Powell, S., Hilker, T., Lawrence, R. (2010) Improved classification of conservation tillage adoption using high temporal and synthetic satellite imagery. Remote Sensing of Environment, 115, 66-754
  45. Wulder, M.A., White, J.C., Stinson, G., Hilker, T., Kurz, W., Coops, N.C., St-Onge, B., Trofymow, J.A. (2010)  Implications of differing input data sources and approaches upon forest carbon stock estimation. Environmental Monitoring Assessment, DOI 10.1007/s10661-009-1022-6
     
    2009
     
  46. Hilker, T., Coops, N.C., Coggins, S.B., Wulder, M.A., Brown, M., Black, T.A., Nesic, Z., & Lessard, D. (2009). Detection of foliage conditions and disturbance from multi-angular high spectral resolution remote sensing. Remote Sensing of Environment, 113, 421-434
  47. Hilker, T., Lyapustin, A., Hall, F.G., Wang, Y., Coops, N.C., Drolet, G., & Black, T.A. (2009). An assessment of photosynthetic light use efficiency from space: Modeling the atmospheric and directional impacts on PRI reflectance. Remote Sensing of Environment, 113, 2463-2475
  48. Hilker, T., Wulder, M.A., Coops, N.C., Linke, J., McDermid, G., Masek, J.G., Gao, F., & White, J.C. (2009). A new data fusion model for high spatial- and temporal-resolution mapping of forest disturbance based on Landsat and MODIS. Remote Sensing of Environment, 113, 1613-1627
  49. Hilker, T., Wulder, M.A., Coops, N.C., Seitz, N., White, J.C., Gao, F., Masek, J.G., & Stenhouse, G. (2009). Generation of dense time series synthetic Landsat data through data blending with MODIS using a spatial and temporal adaptive reflectance fusion model. Remote Sensing of Environment, 113, 1988-1999
  50. Chen, B.Z., Black, T.A., Coops, N.C., Hilker, T., Trofymow, J.A., & Morgenstern, K. (2009). Assessing Tower Flux Footprint Climatology and Scaling Between Remotely Sensed and Eddy Covariance Measurements. Boundary-Layer Meteorology, 130, 137-167
  51. Cheng, Y.B., Middleton, E.M., Hilker, T., Coops, N.C., Black, T.A., & Krishnan, P. (2009). Dynamics of spectral bio-indicators and their correlations with light use efficiency using directional observations at a Douglas-fir forest. Measurement Science & Technology, 20
  52. Middleton, E.M., Cheng, Y.B., Hilker, T., Black, T.A., Krishnan, P., Coops, N.C., & Huemmrich, K.F. (2009). Linking foliage spectral responses to canopy-level ecosystem photosynthetic light-use efficiency at a Douglas-fir forest in Canada. Canadian Journal of Remote Sensing, 35, 166-188
     
    2008
     
  53. Hilker, T., Coops, N.C., Hall, F.G., Black, T.A., Chen, B., Krishnan, P., Wulder, M.A., Sellers, P.J., Middleton, E.M., & Huemmrich, K.F. (2008). A modeling approach for upscaling gross ecosystem production to the landscape scale using remote sensing data. Journal of Geophysical Research-Biogeosciences, 113
  54. Hilker, T., Coops, N.C., Hall, F.G., Black, T.A., Wulder, M.A., Nesic, Z., & Krishnan, P. (2008). Separating physiologically and directionally induced changes in PRI using BRDF models. Remote Sensing of Environment, 112, 2777-2788
  55. Hilker, T., Coops, N.C., Schwalm, C.R., Jassal, R.S., Black, T.A., & Krishnan, P. (2008). Effects of mutual shading of tree crowns on prediction of photosynthetic light-use efficiency in a coastal Douglas-fir forest. Tree Physiology, 28, 825-834
  56. Hilker, T., Coops, N.C., Wulder, M.A., Black, T.A., & Guy, R.D. (2008). The use of remote sensing in light use efficiency based models of gross primary production: A review of current status and future requirements. Science of the Total Environment, 404, 411-423
  57. Hilker, T., Wulder, M.A., & Coops, N.C. (2008). Update of forest inventory data with lidar and high spatial resolution satellite imagery. Canadian Journal of Remote Sensing, 34, 5-12
  58. Hall, F.G., Hilker, T., Coops, N.C., Lyapustin, A., Huemmrich, K.F., Middleton, E., Margolis, H., Drolet, G., & Black, T.A. (2008). Multi-angle remote sensing of forest light use efficiency by observing PRI variation with canopy shadow fraction. Remote Sensing of Environment, 112, 3201-3211
  59. Wulder, M.A., Bater, C.W., Coops, N.C., Hilker, T., & White, J.C. (2008). The role of LiDAR in sustainable forest management. The Forestry Chronicle, 84, 807-826
     
    2007
     
  60. Hilker, T., Coops, N.C., Nesic, Z., Wulder, M.A., & Black, T.A. (2007). Instrumentation and approach for unattended year round tower based measurements of spectral reflectance. Computers and Electronics in Agriculture, 56, 72-84
  61. Coops, N.C., Hilker, T., Wulder, M.A., St-Onge, B., Newnham, G., Siggins, A., & Trofymow, J.A. (2007). Estimating canopy structure of Douglas-fir forest stands from discrete-return LiDAR. Trees-Structure and Function, 21, 295-310
  62. White, J.C., Coops, N.C., Hilker, T., Wulder, M.A., & Carroll, A.L. (2007). Detecting mountain pine beetle red attack damage with EO-1 hyperion moisture indices. International Journal of Remote Sensing, 28, 2111-2121

 

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Remote Sensing of Environment